Development of a Real-Time, HRRR-Like SAR-FV3 System at NOAA/ESRL/GSD

With NCEP moving toward a Unified Forecast System (UFS) paradigm to streamline its operational suite, the Finite Volume Cubed Sphere (FV3) model was chosen as the common dycore under which to consolidate modeling efforts across NOAA. Part of this transition has included work on a stand-alone regional (SAR) version of the FV3, with collaborative development taking place between GSD, EMC, NSSL, and NCAR. The ultimate goal at GSD is to develop a SAR-FV3-based Rapid-Refresh Forecast System (RRFS) that will include all data assimilation, model, and diagnostic components of the current RAP, HRRR, and HRRRE.

To this end, a real-time SAR-FV3 system, running with a HRRR-like domain has been developed, including initial/boundary conditions from the HRRR/RAP, and GSD physics implemented through the Common Community Physics Packages (CCPP). Currently running in a cold-start configuration, 36-hr forecasts are generated at both 00 and 12Z, with preliminary verification being conducted through the Model Analysis Tool Suite (MATS), and real-time graphics of select variables available on the GSD HRRR website. Evaluation of this real-time system will allow GSD to assess the ability of the SAR to forecast convective phenomena, among others, and provide a baseline for future development work.